Questions tagged [coin-tossing]
A puzzle about flipping/tossing coins. Typical examples are about the probability that head or tail comes out.
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Winning chance in coins game with fixing
A player plays the following solitaire game. The game consists of as many rounds as are needed to produce a result. They have 20 fair coins, which may in any round be live or fixed; each coin starts ...
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You are at a crossroads with five roads leading away from it
To allow new users to solve this puzzle and earn reputation points, I encourage all users whose reputation is 200 or more to not post an answer until 48 hours after this question is posted. Thank you!
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Choose the wine
I based this on a problem from a mathematics presentation, adding a small twist. I did not readily find it here.
Your friend comes to dinner and you know he loves to drink Beaujolais. You have 'Cote ...
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Extension to the coin flipping puzzle
This is an extension to this great puzzle: Coin Flipping Puzzle. The main difference is we now have ternary sequences instead of binary sequences.
Two criminals $A$ and $B$, were recently captured and ...
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Coin Flipping Puzzle
This is a repost from my post at Math Stack Exchange
2 criminals A and B, were recently captured and brought to prison. They were then locked in two separate rooms.
Known for being exceedingly smart, ...
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Simulating a biased coin with an unbiased one
You are given an unbiased fair coin, ie., a coin that produces heads with probability 0.5. Can you use this coin to simulate a biased coin that produces heads with some given probability $p$ ?
This is ...
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Simulating an unbiased coin with a biased one
You are given a biased coin. With probability $p$ it produces heads, where $p$ is in the range $(0,1)$. How can you use this coin to simulate an unbiased fair coin, ie., a coin that produces heads ...
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Find the unseen numbers of two tokens after then have been tossed, given sums [closed]
The puzzle is as follows:
Over a table there are two flat tokens. Each one has a number written
in both of their faces. If both chips are tossed and the remaining
numbers seen to the eye are added ...
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Guess the coin toss [duplicate]
You and your friend are put in two different rooms with just a coin and no way to communicate. You both toss the coin at the same time.
Your task is for at least one of you to guess correctly what ...
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Truly Fair Coin [closed]
Is there such a coin – or cylinder – in which there is an equal chance of getting heads, tails or landing on its side? I am guessing that it is a ratio between the radius and height of the coin, but ...
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Frequentists be damned! Design an evil coin to prove a point [closed]
The frequentists' definition of a "fair coin" is a coin that, tossed a million times, converges toward an equal number of heads and tails.
But what is meant by converges? We might imagine a plot of ...
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100 coins (Heads and Tails) [duplicate]
"You have a 100 coins laying flat on a table, each with a head side
and a tail side. 10 of them are heads up, 90 are tails up. You can't
feel, see or in any other way find out which side is up. ...
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More coin flipping
After their last game, Alice and Bob decide to have a bit more fun with their fair coin. Bob proposes the following game: considering a flip can come out as heads or tails, they will both predict one ...
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The asymmetric coin game
After finding a coin in her farm, Alice proposes the following game to Bob:
Alice will flip the coin $n$ times. Bob will then flip the coin $2n$ times. If Bob manages to get the same amount of ...
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No two heads in a row
Suppose I toss a fair coin a 100 times.
What is the probability of not getting two heads in a row?
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